Rice Farm Road Bridge

Carrying Rice Farm Road (Town Highway 62) across the West River, two miles south of Dummerston, Vermont is a rare, intact quadruple intersection Warren (Hilton) throughtruss bridge, built by the Berlin Iron Bridge Company and dating to 1892. The 14.2 foot wide single span stretches 198 feet in sixteen panels across the river 24 feet below, and has a portal clearance of 21.4 feet. The Hilton Truss, known for its rigidity and impact resistance, remains in its original location on abutments which appear to be constructed of granite quarry scraps, and retains its integrity of location, design, materials, workmanship, feeling and association

Within sight of the quarry it was built to serve, this riveted, Hilton through-truss with a northeast-southwest orientation, carries a single lane across the West River. The top chord is a 9 inch by 14 inch box-girder formed of angles and channels, with stay plates on the underside, every four feet. The top chords are joined by crossed pairs of angle section providing lateral bracing. The end posts are inclined and are identical in construction to the top chord box-girder. The portals themselves are braced with lattice between T-struts, and T-Section knee braces. The bottoms of the end posts are reinforced with channel sections. The main diagonals and hip verticals are paired angles joined by stay plates spaced 60 inches on center. The hip vertical and the first two diagonals originate from the top chord hitch plates. The reverse diagonals are paired angles joined by lattice bars. The bottom chords are paired, 12 inch deep, built-up channels with stay plates 72 inches on center. The bottom chords carry a floor system of rolled I-section floor beams spaced approximately 18 inches on center, and they in turn carry a steel grill deck. On the bottom of the lower chords, angle-section lateral bracing similar to the top chord bracing adds rigidity. Guardrails on each side of the bridge are bolted to the trusses. These are composed of a square tubing top rail supported by square tube stanchions, a fender rail about 10 inches wide, and a wheel guard welded to the stanchions at deck level.

STATEMENT OF SIGNIFICANCE

Built in 1892, the Hilton Through Truss bridge, which bears Rice Farm Road across the West River, south of Durnrnerston, Vt., is one of the oldest metal truss bridges in Vermont. It is submitted as part of Multiple Property Documentation Form: Metal Truss, Masonry and Concrete Bridges in Vermont as a metal truss bridge property type, and carries state-wide significance under National Register criterion A and C. The bridge is highly significant because it displays a rare use of railroad engineering to meet a unique road-building situation; carrying carts laden with quarried granite across the White River. Further, it is a rare survivor of the flood of 1927, which destroyed some 1200 bridges state-wide, and therefore was not a part of the .post-diluvian standardization movement in bridge construction, which characterized the rebuilding campaign. Finally, It was constructed by one of the largest bridge builders in New England and at the time was notable for its innovative design, length and construction methods.

The bridge is significant under Criteria A as a part of Vermont's growing road network in the late 19th century. The creation of modem roads was instrumental in the growth of both local and nation-wide trade and commerce in what had long been a commercially isolated state. Specifically, this bridge was built to serve the George E. Lyon Granite Company. The company produced one of Vermont's most famous and celebrated products, and the bridge was built during a particularly innovative and prosperous time, when new equipment was making possible the quarrying of single stones of previously unmanageable sizes.

The bridge is significant under Criteria C because of both its unique structural design, and the status of its manufacturer. The Hilton Truss, a quadruple intersection Warren Truss, uses a multiple intersection design developed for railway use. Although the Hilton Truss was criticized for being excessive in its use of materials and for the inability to accurately measure the load limits of its design, the extra diagonals added rigidity and impact resistance. The configuration of closely spaced crossbeams resting directly on the lower chord was devised to support heavy moving loads such as trains. All of these factors made the design stable and longwearing. The traits which made the Hilton truss suitable for railroads, also made it suitable for supporting the large granite blocks that Lyon's was shipping. Finally, the bridge is an early example of the use of riveting in bridge building.

The bridge is also significant because of its association with an important manufacturer, The Berlin Iron Bridge Co. which, until 1900 was the largest bridge builder in New England. The span is an unusual example of a riveted bridge by the Berlin Iron Bridge Company which was best known for its lenticular pinned trusses. Such an example by the Berlin company is also significant, because in 1900 the company was acquired by the American Bridge Co. whose nation-wide operations would make riveted bridges the standard of the day. Finally, the bridge was long for its time, and was considered important enough to be included in the Berlin Iron Bridge Co. catalog of 1892.